ATTACHMENT C

AIR POLLUTION CONTROL DISTRICT

COUNTY OF SAN DIEGO

PROPOSED

REDESIGNATION REQUEST AND MAINTENANCE PLAN FOR THE

1997 NATIONAL OZONE STANDARD

WORKSHOP REPORT

A workshop notice was distributed to all e-mail subscribers, local Economic Development 

Corporations and Chambers of Commerce, the U.S. Environmental Protection Agency (EPA), 

the California Air Resources Board (ARB), and other interested parties.

The workshop was held on September 28, 2012, and was attended by eight people. The 

workshop comments and Air Pollution Control District (District) responses are as follows:

1. WORKSHOP COMMENT

What is the region's compliance status regarding the national 1-hour ozone standard? Will 

that status be affected by the Redesignation Request for the 1997 national 8-hour ozone 

standard?

DISTRICT RESPONSE

San Diego County attained the national 1-hour ozone standard (0.12 parts per million) in 

2001. Accordingly, the EPA redesignated the region to an attainment area for the national 1-

hour ozone standard in 2003, at which time the EPA also approved San Diego County's 

Ozone Maintenance Plan for that standard.

The region's attainment designation for the now-revoked national 1-hour ozone standard is 

unaffected by the proposed Redesignation Request for the 1997 8-hour ozone standard. 

Nevertheless, if the region is redesignated to an attainment area for the 1997 8-hour ozone 

standard (as proposed), then the proposed Maintenance Plan for that 8-hour ozone standard 

will replace the Maintenance Plan for the 1-hour ozone standard as the currently applicable 

Ozone State Implementation Plan (SIP) for San Diego County. The expected change in the 

region's applicable Ozone SIP will have little impact in the region because there would be no 

resulting change in emission control requirements.

2. WORKSHOP COMMENT

The emission inventories reflected in Table 4-1 show a slight increase in stationary source 

emissions between the 2002 base year and the 2011 attainment year. This increase seems 

counterintuitive in light of the substantial past and ongoing efforts to regulate and reduce 

emissions from stationary sources.
Workshop Report

Ozone Redesignation Request and Maintenance Plan

C - 2

DISTRICT RESPONSE

The emissions inventory reflects general regional growth between 2002 and 2011. The 

District’s stationary source control programs had mostly already been implemented and 

provided significant emissions reductions prior to the 2002 base year, rather than during the 

2002-2011 period.

Please also refer below to the District Response to Workshop Comment No. 3.

3. WORKSHOP COMMENT

The enhanced vapor recovery program at gas stations was implemented between 2002 and 

2011. Why does Table A-1 (Emissions Inventories) show an increase in emissions from 

Petroleum Marketing between 2002 and 2011?

DISTRICT RESPONSE

There have been no updated emission factors approved by the ARB as of yet for use in the 

emissions inventory to reflect the reduced emission rates attributable to the Enhanced Vapor 

Recovery Program. Consequently, the emissions inventory does not yet reflect total emission 

reductions that have occurred from implementation of the Enhanced Vapor Recovery 

Program.

4. WORKSHOP COMMENT

The Contingency Plan (Section 5.7) within the proposed Maintenance Plan specifies that the 

District is retaining the current New Source Review (NSR) emission offset requirement, 

which surpasses a contingency requirement in EPA policy guidance. Since the NSR offset 

requirement is already in effect and is not being reserved as a contingency measure, it should 

not be identified in the Contingency Plan.

DISTRICT RESPONSE

The District agrees. The proposed Contingency Plan has been revised to omit references to

the District's existing NSR emission offset requirement. NSR emission offsetting is 

applicable to new or modified major stationary sources of nonattainment pollutants and 

precursors. It is required as a contingency measure only in areas that, upon redesignation to 

attainment, transition from NSR to less-stringent Prevention of Significant Deterioration 

(PSD) requirements that apply (in lieu of NSR) to attainment pollutants. However, due to the 

region's current nonattainment of the 2008 national ozone standard, NSR emission offsetting 

will continue to apply upon redesignation to attainment of the 1997 ozone standard. 
Workshop Report

Ozone Redesignation Request and Maintenance Plan

C - 3

Therefore, the requirement to identify NSR emission offsetting as a contingency measure

currently does not apply to this region.

5. WORKSHOP COMMENT

What is the California Advanced Clean Cars Program that is in the Contingency Plan?

DISTRICT RESPONSE

California’s Advanced Clean Cars Program, adopted by the ARB in January 2012, integrates

and further tightens control requirements for smog-forming emissions and greenhouse gases

from light- and medium-duty on-road motor vehicles, including increased requirements for 

zero-emission vehicles. The Advanced Clean Cars Program is expected to provide about 2 

tons per day additional reductions in each ozone-precursor pollutant by 2025 in San Diego 

County. Since the anticipated emission reductions from the Advanced Clean Cars Program

are not reflected in the maintenance demonstration, they are surplus and therefore are eligible 

as a contingency measure.

RR:jlm

10/01/12